If a man performs Zihar concerning his slave wife, and subsequently gains full ownership (by purchase or gift) before expiating, what is the ruling on their marriage and relations?

Primary text

Zihar is validly pronounced against every wife, whether she is a free woman or a slave. If a man performs Zihar against his slave wife and subsequently acquires her ownership, the marriage contract is annulled. The established position, affirmed by Al-Khiraqi, Malik, Abu Thawr, the Ashab al-Ra'y, and Al-Shafi'i, is that the ruling of Zihar remains in effect, and he is not permitted to have marital relations with her until he performs the atonement. This is based on the saying of God Almighty: 'And those who pronounce Zihar upon their wives and then return to what they have said must free a slave before they touch each other' (Quran 58:3). Since he has performed Zihar against his wife, she remains untouchable until atonement is made. Furthermore, the ruling of Zihar, having been correctly established, is not invalidated by divorce which removes ownership and permissibility; thus, it is more certainly retained when ownership (milk al-yamin) is established.